Introduce PrefRegistrySyncable, simplifying PrefServiceSyncable.

chrome/browser/prefs/session_startup_pref.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_PREFS_SESSION_STARTUP_PREF_H__
 #define CHROME_BROWSER_PREFS_SESSION_STARTUP_PREF_H__
 
 #include <vector>
 
 #include "googleurl/src/gurl.h"
 
 class PrefService;
-class PrefServiceSyncable;
+class PrefRegistrySyncable;
 class Profile;
 
 // StartupPref specifies what should happen at startup for a specified profile.
 // StartupPref is stored in the preferences for a particular profile.
 struct SessionStartupPref {
   enum Type {
     // Indicates the user wants to open the New Tab page.
     DEFAULT,
 
     // Deprecated. See comment in session_startup_pref.cc
@@ skipping 10 matching lines @@
     TYPE_COUNT
   };
 
   // For historical reasons the enum and value registered in the prefs don't
   // line up. These are the values registered in prefs.
   static const int kPrefValueHomePage = 0;  // Deprecated
   static const int kPrefValueLast = 1;
   static const int kPrefValueURLs = 4;
   static const int kPrefValueNewTab = 5;
 
-  static void RegisterUserPrefs(PrefServiceSyncable* prefs);
+  static void RegisterUserPrefs(PrefRegistrySyncable* registry);
 
   // Returns the default value for |type|.
   static Type GetDefaultStartupType();
 
   // What should happen on startup for the specified profile.
   static void SetStartupPref(Profile* profile, const SessionStartupPref& pref);
   static void SetStartupPref(PrefService* prefs,
                              const SessionStartupPref& pref);
   static SessionStartupPref GetStartupPref(Profile* profile);
   static SessionStartupPref GetStartupPref(PrefService* prefs);
@@ skipping 22 matching lines @@
   ~SessionStartupPref();
 
   // What to do on startup.
   Type type;
 
   // The URLs to restore. Only used if type == URLS.
   std::vector<GURL> urls;
 };
 
 #endif  // CHROME_BROWSER_PREFS_SESSION_STARTUP_PREF_H__